1. Field of the Invention
The present invention relates to an image processing apparatus for applying video special effects to input image signals and, more particularly, to an apparatus having a key frame function.
2. Description of the Prior Art
There have been known heretofore a variety of special effect apparatus adapted to process an input image signal in a wipe, fade or other video special effect mode, as disclosed in U.S. Pat. No. 4,199,788 for example. Also known is a special effect apparatus having a key frame function wherein, if a round pattern is specified at points A and B as illustrated in FIG. 1, there is attainable an effect of shifting the round pattern automatically from the point A to the point B in a predetermined time. The key frame is a function for producing, by automatic interpolation, data between the states in a special effect process such as a pattern shift, wipe or fade mode.
There is further known another type that executes video special effect processes to input image signals in a plurality of signal processors. However, since merely one key frame list is applied to the plural signal processors in such conventional special effect apparatus, it is impossible to perform the key frame functions independently of one another in the individual signal processors, hence causing difficulties in preparation of key frame lists for complicated shifts of patterns.